What is covariance and contravariance?
Experience Level: Senior
Tags: .NETASP.NET MVCASP.NET WebAPIASP.NET WebFormsC#
Answer
Covariance
Covariance enables you to pass a derived type where a base type is expected.
- Co-variance is like variance of the same kind.
- The base class and other derived classes are considered to be the same kind of class that adds extra functionalities to the base type. So covariance allows you to use a derived class where a base class is expected.
Hint: can accept big if small is expected.
Links
https://blogs.msdn.microsoft.com/ericlippert/tag/covariance-and-contravariance/
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